Published 12/1/2018

Second Look—Clinical

Hip and knee

Frailty and THA outcomes
Patient frailty increased mortality and perioperative complications following primary and revision total hip arthroplasty (THA), according to a study published in The Journal of Arthroplasty (online). The study included 6,502 primary THA patients and 2,138 revision THA patients (median age, 68 years). Overall, 22.7 percent were classified as frail, 32.9 percent as vulnerable, and 44.4 percent as nonfrail. Frail patients were more likely to be female, older, and sicker, and they received more general anesthesia. Frail patients had increased risks of wound complications/hematoma and reoperation while in the hospital compared to nonfrail patients. At 90 days and one year, frail patients had greater risks of mortality, infection, dislocation, wound complication/hematoma, and reoperation. The researchers found no significant associations with aseptic loosening, periprosthetic fracture, or heterotopic ossification.

Mortality in hip arthroplasty based on BMI—Underweight hip arthroplasty patients may have an increased mortality rate one year after surgery, according to a study published in Age and Ageing (online). The study included 3,627 hip arthroplasty patients who underwent surgery between 2010 and 2013. Researchers used Cox regression analysis to observe any correlation between body mass index (BMI) and mortality from 30 days, from 31–365 days, and from the first day of surgery until death during the study. Compared to those with normal BMI, underweight patients (BMI, < 18.5 kg/m2) had a significantly higher risk of death. Short-term analyses showed that within 30 days of operation, underweight and obese (BMI, 25–29.9 kg/m2) patients had an increased mortality rate.

Choosing PJI treatment—In a study published in The Journal of Arthroplasty (online), primary arthroplasty patients who sustained prosthetic joint infection (PJI) were more likely to have their hardware removed when treated at a different hospital than patients who received treatment at the investigating institution. Researchers analyzed 270 patients with primary THA and total knee arthroplasty infections. When controlling for confounding factors, they found that patients whose index procedures were performed at outside hospitals were more likely to choose prosthetic removal for treatment than patients who underwent total arthroplasty at the investigating institution. The researchers suggested that institutional protocols be put in place to guide the decision-making process and avoid bias.

LMWH after THR or TKR
A study published in BMC Musculoskeletal Disorders (online) compared outcomes for total hip replacement (THR) and total knee replacement (TKR) patients who received low-molecular-weight heparin (LMWH) versus other anticoagulants, direct thrombin inhibitors, or placebo. Researchers conducted a review of Medline, Cochrane, EMBASE, and Google Scholar to identify 21 randomized, controlled trials published before June 30, 2017. They found that THR patients who received LMWH had a lower risk of venous thromboembolism (VTE) and deep vein thrombosis (DVT) than the placebo group; however, rates of pulmonary embolism (PE) risk were similar between the groups. TKR patients who received LMWH had a higher risk of VTE than those receiving factor Xa inhibitors. Among THR and TKR patients, LMWH was associated with greater DVT risk than factor Xa inhibitors, but major bleeding and PE risks were similar. For both THR and TKR, risks were similar between the LMWH and direct thrombin inhibitor cohorts for VTE, DVT, and PE. Major bleeding was lower for THR patients in the LMWH group but similar for TKR patients.

Patellofemoral disease’s effect on UKA outcomes—The results of a prospective study published in Knee Surgery, Sports Traumatology, Arthroscopy (online) found that the presence of patellofemoral disease at the time of unicompartmental knee arthroplasty (UKA) did not affect long-term implant survival 10 years postoperatively. Researchers followed 216 patients (263 knees) who underwent UKA between 2003 and 2005. Patellofemoral disease was present in 41 knees (15.6 percent), and 222 knees (84.4 percent) had normal patellofemoral joint state. After 10 years, the normal and patellofemoral groups had similar Oxford Knee Scores (20 versus 20, respectively) and Knee Society Scores (79 versus 81, respectively). The normal group had 12 revisions, half of which were performed for contralateral compartment osteoarthritis (OA), and the patellofemoral group had one revision for contralateral compartment OA. When labeling all secondary surgeries as failures, the 10-year survival rate was 95.1 percent.

Fractures after THA using uncemented stems—A study published in The Journal of Arthroplasty(online) found that periprosthetic femoral fracture (PFF) could be the most likely long-term failure following uncemented THA with a tapered titanium stem. Authors of the long-term study retrospectively reviewed 354 hips that underwent uncemented THA with a tapered titanium stem. At mean follow-up of 28 years, 184 hips were unavailable for review. In the remaining hips, 27 fractures occurred; 15 hips required stem revision, 10 were treated by open reduction and internal fixation, and two patients declined surgery. PFF probability was 1.6 percent at 10 years and 13.2 percent at 29 years following primary THA. Researchers observed no correlation between fracture and sex, age at time of operation, cup revision, or canal-fill-index.

ACL tears and late-life comorbidities—A study published in The American Journal of Cardiology (online) observed a possible correlation between anterior cruciate ligament (ACL) tears and nonmusculoskeletal effects later in life.

The study included former NFL players (n = 3,506) with self-reported physician-diagnosed health conditions. The researchers estimated hazard ratios for joint replacement surgeries, myocardial infarction, sleep apnea, arthritis, dementia, and stroke by history of ACL tear during the players’ professional careers. Former NFL players who tore an ACL had approximately a two-fold increase in musculoskeletal comorbidities, including knee joint replacement and arthritis compared to those without ACL tears. ACL tears also were associated with an increased risk of myocardial infarction and sleep apnea.

Predictors of perioperative adverse outcomes in THA—A retrospective cohort study published in the Journal of the AAOS (Oct. 15) found that a patient’s age and American Society of Anesthesiologists (ASA) class were the factors most predictive of adverse outcomes after THA. Researchers identified 64,792 THA patients (mean age, 64.8 years; 55.2 percent female) and compared their ASA class, modified Charlson Comorbidity Index, modified Frailty Index, and demographic characteristics. Perioperative outcomes consisted of any adverse event (AE), severe AEs, minor AEs, extended hospital stay, and discharge to higher-level care. ASA was the most predictive comorbidity index, and age was the most predictive demographic factor. Between the two, age was the best indicator in four of the five adverse outcomes.

Arthroscopic partial meniscectomy complications—Arthroscopic partial meniscectomy is considered a low-risk procedure, but there is a risk for a few rare yet serious complications, according to a study published online in The Lancet (online). Researchers searched the national Hospital Episode Statistics for data on arthroscopic partial meniscectomies performed in England between April 1, 1997, and March 31, 2017, excluding simultaneous or staged (within six months) bilateral cases. They included 699,965 total procedures. Within 90 days, complications arose in 2,218 cases (0.317 percent), including 944 infections that required further surgery (0.135 percent) and 546 pulmonary emboli (0.078 percent). Older age, male sex, and more comorbidities were associated with increased complication risk. Mortality risk decreased over time. The general population had a greater risk of mortality, myocardial infarction, and stroke than the study cohort. Researchers estimated that for every 1,390 fewer knee arthroscopies performed, one pulmonary embolism may be avoided, and for every 749 fewer operations, one native knee joint infection may be avoided.

Dislocation risk factors after revision THA—A literature review published in the Journal of Orthopaedics and Traumatology (online) found that the use of larger femoral and acetabular components, elevated rim liners, and dual mobility implants may reduce the risk of dislocation following revision THA. Researchers reviewed 33 articles to identify risk factors for dislocation. In addition to the use of larger prosthetic components, constrained bearing inserts may be used as a salvage procedure because, although they reduce the rate of dislocation, they do not reduce the rate of re-revision. Although using certain components intraoperatively may minimize risk, patient-related risk factors such as abductor deficiency, a history of instability, and complex acetabular defect also should be considered and evaluated prior to surgery.

Teriparatide and hip fractures—A meta-analysis published in Bone (online) found that patients with osteoporosis treated with teriparatide had a lower risk of hip fracture but not upper limb fractures. Researchers gathered data from 23 randomized clinical trials, comprising 8,644 patients with osteoporosis, of whom 3,893 were treated with teriparatide. Mean age was 67.0 years, and median treatment duration was 18 months. Fractures included incident hip (n = 34), humerus (n = 31), forearm (n = 31), and wrist (n = 62). Teriparatide reduced hip fractures by 56 percent. Risk of humerus, forearm, and wrist fractures did not significantly differ between the teriparatide and control groups.

NLR for relapse in pigmented villonodular synovitis—Preoperative neutrophil-to-lymphocyte ratio (NLR) may be an easy, cost-effective way to predict relapse in pigmented villonodular synovitis (PVNS) of the knee joint following arthroscopic synovectomy followed by local radiotherapy, according to a study published in BMC Musculoskeletal Disorders (online). Among 60 pathologically proven PVNS knee joint cases treated between April 2006 and March 2017, the recurrence rate at mean follow-up (52.8 months) was about 23.3 percent (n = 14). Researchers observed a correlation between NLR and postoperative recurrence. The receiver operating characteristic curves indicated that an NLC higher than 2.42 was strongly predictive of recurrence (sensitivity, 71.4 percent; specificity, 78.3 percent).

PT and nonobstructive meniscal tear—Physical therapy (PT) may not be inferior to early operative treatment of arthroscopic partial meniscectomy (APM) for improving knee functionality in patients with nonobstructive meniscal tears, according to a study published in JAMA (online). The randomized clinical trial included 321 patients aged 45 to 70 years who had nonobstructive meniscal tears and were treated at nine hospitals in the Netherlands between July 17, 2013, and Nov. 4, 2015. Patients were treated with APM (n = 159) or a predefined PT protocol (n = 162) that included 16 exercise therapy sessions over eight weeks. PT sessions focused on coordination and closed kinetic chain strength exercises. At 24-month follow-up, knee functionality in the PT group improved by 20.4 points compared to 26.2 points in the APM group. The difference did not exceed the noninferiority margin.

Shoulder and elbow

Shoulder OA outcomes and orthopaedic specialists—In a retrospective study published in BMC Musculoskeletal Disorders (online), patients with shoulder OA received faster and more invasive treatment when they received a new diagnosis from an orthopaedic specialist (OS) versus a nonorthopaedic physician (NOP). The study included patients with shoulder OA (n = 572) who had received care from either an OS (n = 474) or NOP (n = 98) on the date of their index shoulder visit. OS patients received their first treatment significantly more quickly than the NOP cohort (16.3 days versus 32.3 days, respectively). The OS group also had higher rates of operative treatment within one year following their initial visit.

Predictors of pain after TSA—Total shoulder arthroplasty (TSA) patients with self-reported allergies, preoperative chronic opioid use, lower American Shoulder and Elbow Surgeons (ASES) score, and depression may be more likely to experience severe postoperative pain, according to a study published in the Journal of Shoulder and Elbow Surgery (online). Researchers evaluated preoperative characteristics associated with severe pain, including demographics, emotional health, comorbidities, and ASES score in patients undergoing elective primary TSA. Patients with severe postoperative pain took more opioids (202 versus 84 mg oral morphine equivalents), had longer hospital stays (2.9 versus 2.0 days), used postacute inpatient rehabilitation services more often (28 percent versus 10 percent), and were more likely to be high-cost patients (23 percent versus 5 percent) than patients without severe postoperative pain. Surgery length did not differ between the two groups.

Isolated supraspinatus tendon repair—Two decades after operative treatment for isolated supraspinatus tears, clinical outcomes still greatly surpassed preoperative conditions, according to a retrospective study published in the Journal of Shoulder and Elbow Surgery (online). The study included 137 patients; six (4.3 percent) died from unrelated causes, 52 (38 percent) were lost to follow-up, and 13 (9.5 percent) had undergone reoperations. Among the remaining 66 patients available for clinical evaluation, 45 patients underwent radiography and MRI to assess OA, tendon healing, fatty infiltration (FI), and muscle atrophy. The Constant Score went from 51.5 points preoperatively to 71 points at follow-up. Tendon discontinuity presented in 42 percent of patients (n = 19), advanced FI of the supraspinatus muscle in 27 percent (n = 12), FI of the infraspinatus muscle in 35 percent (n = 16), supraspinatus atrophy in 28 percent (n = 12), and cuff tear arthropathy in 30 percent (n = 12). Six patients had advanced arthritis. Infraspinatus FI was the factor most influential on long-term clinical outcome.

Shoulder OA with tendon degeneration—Shoulder OA patients had a higher incidence of macroscopic degeneration than those without shoulder OA in a study published in Knee Surgery, Sports Traumatology, Arthroscopy (online). Patients with shoulder OA (n = 13) or a proximal humerus fracture (control, n = 13) underwent an open biopsy procedure from the biceps and subscapularis tendon in conjunction with shoulder arthroplasty. Fifteen of the 26 specimens in the OA group had macroscopic degeneration compared to seven of 25 in the control group. Total degeneration score did not significantly differ between the groups. The OA group had a greater presence of nonhomogeneous extracellular matrix. Compared to the control group, OA patients had a significantly larger fibril diameter in the biceps tendon but not in the subscapularis tendon.

Synthetic polytetrafluoroethylene patch for rotator cuff repair—In a retrospective cohort study published in The American Journal of Sports Medicine (online), patients with irreparable rotator cuff tears had positive clinical outcomes when treated with a synthetic polytetrafluoroethylene patch to bridge the tear. Researchers assessed 58 patients with a synthetic patch inserted as an interposition graft for large and/or irreparable rotator cuff tears. Shoulder pain, function, range of motion, and strength were assessed preoperatively and at six weeks, 12 weeks, six months, and a minimum of two years postoperatively. At mean 36-month follow-up, 90 percent of patches (n = 53) were still in place. Three patches failed at the patch-tendon interface, and one patient (two shoulders/patches) required reverse total shoulder replacements. At six months, patient-ranked shoulder stiffness, frequency of pain with activity and sleep, level of pain at rest and overhead, and overall shoulder function improved from bad to very good. At minimum two-year follow-up, the most significant strength increases were supraspinatus and external rotation. The greatest improvement in passive range of motion occurred between 12 months and final follow-up.


BMI and SSI after posterior cervical instrumented fusion—A retrospective cohort study published in The Spine Journal (online) found that trauma and nontrauma patients had the same rate of surgical site infection (SSI) after posterior cervical instrumented fusion (PCIF), and all patients with increased BMI were at higher risk for SSI. Researchers assessed data on 1,143 patients who underwent PCIF for traumatic (n = 688) and nontraumatic (n = 454) injuries between April 2011 and October 2017. SSI incidence among all patients was 3.9 percent, with no significant difference in SSI rate between the trauma and nontrauma groups. Diabetic patients and those with BMI ≥ 30 kg/m2 had an increased SSI risk. Patients with both diabetes and higher BMI had an even greater likelihood of developing SSI after PCIF.

Bariatric surgery and posterior lumbar fusion complications—Bariatric surgery prior to elective posterior lumbar fusion could reduce a patient’s risk of medical complications and infection, but patients with higher BMI may remain at increased risk of infection, revision surgery, and readmission compared to patients with normal BMI, according to a study published in The Spine Journal (September). The retrospective cohort study included 156,517 patients undergoing posterior lumbar fusion surgery. Patients were categorized as having a history of bariatric surgery and obesity (n = 590), severe obesity (BMI > 40 kg/m2, n = 5,791), or normal weight (BMI < 25 kg/m2, n = 150,136). Researchers measured 30-day medical complications, surgical complications, death, readmission, and hospital length of stay (LOS). Compared to the severely obese group, bariatric surgery patients had significantly lower rates of respiratory failure, urinary tract infection, acute renal failure, overall medical complications, infection, and hospital LOS. Bariatric surgery and nonobese patients did not have significant differences in medical complications, but the bariatric surgery group had higher rates of infection, reoperation, and readmission.

Postoperative bracing after spinal surgery—According to a literature review published in The Spine Journal (September), bracing after neck or back surgery may not improve outcomes. Researchers conducted a systematic search of MEDLINE, Embase, and the Cochrane Collaboration Library from 1970 to May 2017 and manually searched the reference lists of relevant studies and previously published reviews. They selected literature that compared disability, quality of life, functional impairment, radiographic outcomes, cost-effectiveness, or complications between patients treated postoperatively with bracing or without. Based on low to moderate evidence, researchers found no significant differences in most measures of disability, pain, quality of life, functional impairment, radiographic outcomes, or safety between the groups. In isolated studies, significant and inconsistent differences were observed for Neck Disability Index at six weeks postoperatively or Short Form-36 Physical Component Score at 1.5, three, six, and 12 months postoperatively.

FRAX score predicts vertebral fracture—A retrospective study published in Bone (online) found that an elevated score on the Fracture Risk Assessment Tool (FRAX) was predictive of vertebral fracture in patients with multiple myeloma. Researchers collected data from patients (median age, 61 years) enrolled in Total Therapy Protocols (TT4 and TT5) between August 2008 and September 2017. They calculated FRAX scores and obtained baseline positron emission tomography and MRI imaging. For TT4 patients (low-risk myeloma), the median major osteoporotic score (MOS) was 5.6 compared to 6.2 for TT5 patients (high-risk myeloma). The median hip fracture score (HFS) for TT4 and TT5 patients was 0.5 and 0.7, respectively. Patients with increased MOS (> 2) and HFS (> 4.5) were at increased risk for fracture diagnosis.

Low back pain in Parkinson’s disease—An observational study published in the European Spine Journal (online) found that patients with Parkinson’s disease (PD) may be at increased risk for low back pain (LBP) and lumbar degeneration. Researchers assessed LBP in 97 PD patients and 97 controls using the Oswestry Low Back Pain Disability Questionnaire and visual analog scales. LBP was more common among PD patients than controls (87.6 percent versus 62.6 percent, respectively), with longer duration and higher pain intensity. Higher PD stages and motor scores were associated with pain intensity and disability scores. Of the PD patients with LBP, 79.6 percent had lumbar arthrosis, 38.8 percent had scoliosis, and 24.1 percent had spondylolisthesis. Many PD patients with LBP did not receive specialized orthopaedic treatment.

Foot and ankle

Transfibular total ankle replacement—A prospective study published in Foot & Ankle International (online) found that transfibular total ankle arthroplasty (TAA) may be a safe and effective option for patients with ankle arthritis. Researchers followed 89 transfibular TAA patients who underwent surgery between May 2013 and February 2016 and assessed clinical and radiographic outcomes preoperatively and at six, 12, and 24 months postoperatively. At final follow-up, researchers observed significant improvement in patients’ American Orthopaedic Foot & Ankle Society Ankle-Hindfoot Score (from 33.8 to 88.5), visual analog scale rating (from 80.5 to 14.1), and Short Form-12 Physical and Mental Health composite scores (from 29.9 and 43.3 to 47.0 and 53.3, respectively). Ankle dorsiflexion improved (from 6.2 degrees to 24.2 degrees), as did plantarflexion (from 9.6 degrees to 18.1 degrees). There was no radiographic evidence of tibial or talar lucency, and patients maintained neutral ankle alignment. Seven patients underwent reoperation to remove symptomatic hardware (six fibular plates and one syndesmotic screw); two patients had delayed wound healing; and one patient underwent operative débridement, removal of implants, and placement of an antibiotic spacer to treat a postoperative prosthetic infection.

CAAPs and ankle fracture fixation—Ankle fracture fixation with concurrent ankle arthroscopic procedures (CAAPs) may not be more effective in reducing postoperative risk for reoperation than fixation without CAAPs, according to a study published in The Journal of Foot and Ankle Surgery (online). Researchers used the PearlDiver database to identify 32,307 patients who underwent ankle fracture fixation between January 2007 and December 2011; 248 received CAAP and 32,059 did not. There was no significant difference in reoperation rates between the CAAP group and non-CAAP group (7.7 percent versus 8.6 percent, respectively). Of the 19 CAAP patients who underwent reoperation, 13 had arthroscopic débridement and six had either ankle refixation or osteochondral autograft transfer. In the 3,021 non-CAAP reoperations, 83.2 percent were ankle refixations, 14.3 percent were arthroscopic procedures, and 2.5 percent were ankle arthrodeses. No complications were reported in the CAAP group; complications in the non-CAAP group included wound dehiscence (2.4 percent), deep vein thrombosis (0.8 percent), and pulmonary embolism (0.4 percent).

Sports and exercise

Youth sports and bone mass—Adolescents who engage in organized sports could have greater bone mineral content (BMC) later in life, according to a study in the Journal of Bone and Mineral Research (online). Parents provided information on organized sport participation for 984 children (48 percent female) aged five, eight, 10, 14, and 17 years. Females were categorized as “consistent sport participators” (48 percent), “dropouts” (34 percent), and “nonparticipators” (18 percent), whereas males were classified as “consistent sport participators” (55 percent), “dropouts” (37 percent), and “sports joiners” (8 percent). At age 20, “consistent sport participator” females had much greater leg BMC compared to “dropouts.” For males at age 20, “consistent sport participators” had significantly greater whole-body BMC than “dropouts,” and “sports joiners” had increased leg BMC compared to those who dropped out.

Low back and knee pain in young baseball players—A cross-sectional study published in Knee Surgery, Sports Traumatology, Arthroscopy (online) found that young baseball players with knee pain may be more likely to report LBP. The study used a self-report questionnaire and included 1,609 participants aged 6 to 15 years. The point prevalence of LBP was 8.4 percent, and the prevalence of knee pain was 13.1 percent. Researchers found a significant association between knee pain and LBP. Compared to players who did not have knee pain, those with knee pain had an LBP odds ratio of 5.83. The authors recommended that clinicians pay attention to knee complaints in such patients, as they may be able to prevent and treat LBP.

Group exercise for hip and knee replacement—An outpatient rehabilitation group exercise program for patients who had hip or knee joint replacement increased physical activity levels only during the program’s duration, according to a study published in Clinical Rheumatology (online). Patients took part in a six-week outpatient orthopaedic exercise group after total hip or total knee replacement surgery and were evaluated based on the International Physical Activity Questionnaire short form. Researchers used performance-based tests recommended by the Osteoarthritis Research Society International (30-second Chair Stand Test, 40-minute Fast Pace Walk Test, Stair Climb Test, Timed Up and Go Test, and Six-Minute Walk Test) to evaluate physical function. Fifty-four patients underwent assessments at admission, at discharge, and six weeks after group discharge. At group discharge, researchers observed a significant improvement in self-reported activity levels and performance-based measures. Self-reported activity did not improve at six-week follow-up, but fast-paced walking and Six-Minute Walk Test measures continued to improve.


Synovial fluid Gram stain for pediatric septic arthritis—When screening for pediatric septic arthritis (SA), the Gram stain may not be an efficient method, according to a study published in the Journal of Pediatric Orthopaedics (October). Researchers identified 302 patients who underwent incision and drainage for suspected SA between January 2007 and October 2016. They evaluated results of synovial fluid Gram stain, as well as synovial cell count/differential and serum markers. Thirty-four percent of patients (n = 102) had positive synovial fluid cultures, and Gram stain detected a microorganism in 16 percent of patients (n = 47). Gram stain sensitivity was 0.40, and specificity for SA detection was 0.97. The Gram stain misdiagnosed one of every five patients. The authors concluded that the Gram stain result is a poor screening tool for the detection of SA and is particularly ineffective for the detection of Gram-negative organisms.


Indicator of fractures in geriatrics—A study published in Heart (online) found that elevated mid-regional fragments of pro-adrenomedullin (MR-proADM) and pro-atrial natriuretic peptide (MR-proANP) levels may predict fragility in older patients. Researchers followed 5,415 patients (mean age, 68.9 years) enrolled in the Malmö Preventive Project over 8.1 years and evaluated the correlation between C-terminal pro-arginine vasopressin, C-terminal endothelin-1 precursor fragment, MR-proADM, and MR-proANP, as well as incident vertebral, pelvic, and extremity fractures. Vertebral, pelvic, or extremity fracture occurred in 19 percent of patients (n = 1,030). Risk factors included older age, female sex, low BMI, decreased diastolic blood pressure, antihypertensive treatment, and history of fracture. Elevated MR-proADM and MR-proANP levels were independently associated with increased risk of any fracture. Patients in the top quartile of all four measured biomarkers had a two- to threefold increased risk of fracture at any site.

Cataracts and risk of osteoporosis and fracture—A retrospective cohort study published in the Journal of the American Geriatrics Society (online) found a correlation between cataracts and incidence of osteoporosis and fracture. Researchers matched 57,972 cataract patients who had been treated either surgically or nonsurgically with healthy controls. Overall, during follow-up (mean, 6.4 years), cataract patients were more likely to develop osteoporosis or fractures than the control group (n = 17,450 versus n = 12,627, respectively). Specifically, diagnosis of cataracts was associated with increased risks of osteoporosis (43 percent), hip fracture (16 percent), vertebral fracture (25 percent), and other fractures (24 percent). Cataract patients who underwent cataract surgery were at significantly lower risk of developing osteoporosis or fracture than those who did not have surgery.